Method



f May 1mm LFRANNEYETALi j mman o? 'mslm-Twins FLOW' mora 11.11.1.51'4

Filed July 2,1. 192s- ;f

raient-ed. May-.19,1931

COMPANY, .a conrom'rIoN 'or DELAW-Ann METHOD or' racrnrrarme rrow sneu-wams Arplicauon .mea my 2i, 192s. serial Nb. 294,569. l' This invention relates to improvements in le., the bailer 5 shown in Fig. l methods "of facilitating flow' from wells. or thls purpose.

The invention is especially applicable to the :una Rama', or! New iro-ax, n. Y., .amers o. "rameaux, or- ,Oumma canapa, assumons or @Na-Hm TQ STANDARD .om DEvmrmT .may be vi A charge of va gas-generatingchemical'isi'V i cleaning of oil wells in which Adeposits of addedto the acid. This chemical is one which r V5 parairin, calcite, or the like, have obstructed evolves' a large amount of heat by reaction the flow from the oil-bearing formation. with the acid and/0r Water, Vsimu lt aneously Reference is to be made to the accompanyliberating a gas, preferably a, hydrocarbon ing drawings, in which. gas, soluble in theoil. Metallic carhdes are Fig. 1 is a vertical section through. the low- 10 er part of a well, showing a bailer;

Fig; 2 is a similar view illustrating avqell In Fig. l numeral 1 indicates a well casing seated inl fa cap rock 2 overlying an oil sand by ignitin .the gas produced by the reaction.

15 3. lThe bore ofthe well is extended through Any s uita le i ition means may be used,- -the oil sand and the opening 4' in the sand but it is genera ly most convenient to add a ma Abe enlarged as by blasting or reaming. substance which uponcontact with the charge A ailer or agitating device 5 is suspended will spontaneously ignite the gas. This -s'ub- Y in the casing by a cable 6.

l' 2b Fig. 2 shows a packer? carried b the end peroxide, or it may be an alkali metal or the t'ripper` 9 may Vextend' throufh the acking. yielr s oxygen and thus enables the combus# 25 The tripper may be hollow 1f it is intended tion to be; continued independent of the Aair be solid so as to 'prevent any escape of gas.

l '1 -he improved method will be fully underfrom the surface, or cthervvlse.4

3g use lfor increasing production we The iuid level in the well is lowered by confine gas formed by tl1e-reaction (se'e Fig. rapid hailing or pumping to the lowest prac- 2). It' 1s sometimes necessary however, to' tiable point. An 'tubing or other equip-n allow time for the acid to disso ve away an 35 ment inthe well casing is removecland an acid J deposit of calcite from the walls of the -we is introduced into the well by means of a before settin the packer. Also, if considera-4 though the latter may be used where diimolten paraflinand introduce fresh chemif culty is not encourtered due to the formation .cals before setting the packer. In vserious of calcium sulphate. Mixtures of these acids cases, several applications of acidare required mayv 'used g' other acids are operative but 1n general are too expensive. e

4The treating'solution should be. brought into 'contact' with the entire exposed surface described, causes the gas to penetrate out;

of as into the pores ofthe sand.

' taining a solution level 'at the top of the'o'ilby the oil.

The viscosityof the oil is con-.J

i. be provided to'splash the solution a ainst the facilitated. The pressure also. drives the am 5b sand, as' subsequently described. f

best adapted for this purpose.' Calcium carbide, which yield-s acetylene, is preferred.

Aluminum carbide, wh1ch yields methme,V

sand, orif this i-s not practical, agitation may siderably reduced and iow ifs correspondingl DIn some cases We increase the heating eii'ect vstance 'may be a peroxide, such as sodium ofa string of tubing 8. This pac er is of like which produces heatand fi'ame onv conzo the type which is set by the weight of the tub' tact with water. Sodium'peroxide is espeing and released by lifting the tubing.4 A' clall well adapted for-this purpose sincjeit n to run liquid through the tubing,or it may normally available in the well. Additional f 'oxygen or air may be supplied through'pipea stood from the Afollowing descri tion o f its In general, soon after the reagents are rom an oil placed in the Well a removable packer is set 80 'at approximately the top of the oil sand to dump bailer or otherwise. Hydro'chloric ble paraliin. as accumulated on the Walls of 'y .I hacid o r nitricacid is preferred to sulfuric acid, the well, it may be desirable to bail out thel to' remove calcite sufficiently for the entrance` he pressure generated below the packer, as i of the oil sand. This may be done by mainwardly into .the oil sand where it is dissolved or examinto the sand so that it may act upon any u).

ca'lcite or'other deposits whichY cement the t. lsand grains together. Paraiiin,.asphaltoxi dized or saponxtied oil, and other obstructing carbonaceousdeposits, are melted by the heat of reaction. The violent agitation ofthe reaction mass by boiling and escape of gas exerts lngreagent is dum a washing action n thewall of the well.l

`^ 'Vhen the reaction mass'begins to cool, the

packer is removed and the well is bailed'or pumped while thefluids in it are still at a temperature above that at which paran congeals. Bailin should be from the bottom of the well so 'iat all the dislodged obstructing materials are removed. Pumping is then 1 5 started as soon as possible, suction being taken-near the bottom of the well so as to prevent the development. of back pressure by the accumulation of a fluid column."l Since the acid is neutralized or almost neutralized by reaction with theladded chemicals or the calcite, etc., there is no substantial corrosion of the equipment. If the rimary purpose is to generate heat, the aci and gas-forming material may be used in chemically equiva-z lent amounts. If calcite or the like is to be dissolved to increase the porosity of the sand,

acid should be used in excess. A v

The use of' a packer is lgenerally -very advantageous. However, it may sometimes be I I' Y 30 omitted, for example, during the firstI of a series'- of treatments when it is necessary to treat tl-ie well lseveral times in" the mannerdescribed for the removal of very resistant obstructions. It will be 4understood that the I taneously. j o@ v An alternative plan contemplatestreatmentof the well with the rea ents specified, and bythe methods 'proposI in secplence.

f 85 reagents may be added in any order or simul 40' In this procedure, a string of tubing is run into the well, supporting a wall acker at its lower end, designed to close oli t e space between the tubingandouter casin or wall of the well` immediately above the oil sand. A

bailar is provided having a'diameter su-iiiciently small yto permitof its'free passage through the tubing. The iuid in the Well is hailed down as far as may he practicable, and a quantity of acid of suicient 'strength to 50. attack the 'carbonatedeposits on and wiu'iin vthe wall rocks, is introduced. The quantity'- of acid used should b e in excess of that which 'will react with' calcit'e or other deposits. If possible, the volume offacid solution should be. sutiicent tonearly -fill the well to the top of the voilfprodiicing"formation. 1f not feasible, a smaller quantity may be used and the bailer. chui-ned' up and down in it to w splash itthoroughly and repeatedly over the walls. Air'preure is applied through the ltubing tov force the-acid to enfer the pore spaces.' oflthewall pressure so rovided will also 4be assisted tol some 'extentof y the pressure yoni-carbon dioxidegenerated which comprises charging into`- the 'well an y'action ofthe teals.

After-he acid has been ,fe-mea ina-mie wan., 1 jf 1` rocks as'far as the available pressure permit the pressure is relieved at the tubing het -10 and acharge of carbide or other heat-.producped into the well or low ered to the bottom with the bailer. Reaction of this material with the residual .acid and water inthe bottom of the well, will create 75 y heat, which melts parailin and other Solid hydrocarbons on and within-the wall rocks.

The-bauer its withdrawn, and a swab is oper. i

atedlin the tubing-to draw all molten parain and residual acid from the pore-'spaces 'ci .the '80 wall rocks into the well.- The vfluid material is then quickly vhailed out before it has had time to 'coolappreciab1y.

The following is aspecific example of ourA li. 'I

method, as practiced with acid solution and 815y 'gas generation opertin To an oil well containing water, commerat .the same time:

cial concentrated hydrochlorcaeid' and gran- Y' i ular calcium carbide 4are introduced'at the rate of aboutO vpounds each for each 10 .feet 9'9. of sand depth. The acid m'ay be dilute, asv f -even weak acid will' dissolve the mineral carperoxidelare added and within a yfew minutes l a packer is set at about the level of the top l i of the oil sand. The reaction mixture is allowed to remain in the well :for about two v- 1 hours and is then bailedout, after which the same process may be' repeated if necessary. fumpingis begun immediately with an' oil p'oductionofabout tive times that obtained fore treating the een.; The ,yield will or. dinarily be increased three to 'ten times ori` mre connection withthe regeneration vofsurface v oilwells, but it may 'be 'advantageously' apl plied also to mine 'wells for the production of oil, and in other connections. The preceding description is merely illustrative andvarious changes and alternative procedures may be adopted within the scope of the' appended claims in which it is' our intention to claim all novelty inherent in the i invention as broadly as-the prior art permits.

'XVe claim.:-

1. In thechemical treatment of yWells for. l

facilitating ilow therefrom, the 4improvenienti acid and' a .substance evolving heat and lili-- eratinga hydrocarbon gas upon reaction with the acid.

,ico-f e method described is Vmostl useiiful inl v105.A

bonates. Nex t, .abont 5 pounds of sodium" 2. In the chemical l treatment of'wells for facilitating flow therefrom, the improvement which comprises chargin acid and a metallic carbi 'e'.

3. In the chemical treatment of wells for into-the well an facilitating flow therefrom, the improvement i .f

which comprises char 'ng into the well' hy-V droc'hloric acid and a t allie carbidn;

4. n1 the @emi-ce1. treatment of aimaitv "f I l yfor facilitating-dow therefrom, thel improei' ment which .comprises chargn' 4into the well 'an acid and a metallic eax-bi e, and mainf Y 5 taining a pressure upon the zone in which the acidand carbide react, whereby the gas `pro duced is forced outwardly'into the oil-bear f wardly into the oi sand, and removing theV if reaction mass from the Well before the mass Y, has cooled. f v

i 2o 7. Method according to claim 6, in'which the ,acid 4and carbide are usedin amount about r 50 pounds each-for each ten .feet of sand thickness.

8. In thechemical Vtreatment of oil wells 25 for facilitating dow therefrom, the improvement which comprises charginginto the` well' Ian acid and a substance evolving heat and liberatinga hydrocarbon gas upon reaction with the acid, and igniting said gas. 3o 9. Method according to claim' 8, in which .the gas is -i'nited by means .of a substance spontaneous y iniiammnbl'e' on contact with the reactionmixture.. 10.'` Method according to .claim 8, in which i .35 the gas isignite'd spontaneously by a sub stancewhich yields free oxygen on contact with the reaction mixture. 1 1. In the .chemical treatment ofwells for facilitating fion: therefrom, the improvement acid and a substanceevolving heat and libel*-l ating Va hydrocarbon gas upon reaction'with bythe acidso as'to bring the same into intis mate contact with clogging deposits on the f sides of the well. f 12. Method according to claim 11 in which the reactionl is carried on in tliepreseiicel of e water originally .in the well orl 'supplied Y 50 thereto. 13. Method accordinto claim 11 in which the .acid and gas are orced outwardly into' the ol-bearin 4formation. i 'Ii- O RANNEY.

55. v f CHARLES O.

Leonesa flo which comprises charging into the well an 'y lli 

